How to make evenly spaced pillars for a roller coaster track?
This is one approach - (probably not the best one) 


In object mode, create a plane, coplanar with your curve, its width snapped to the curve's bottom ends, and with a height sufficient to accommodate the curve in projection.
Create vertical edge loops in it (CtrlR + Mouse wheel), one loop for each of your columns.
Knife Project your curve onto the plane, and eliminate unwanted vertices
Duplicate the set of edges comprising the cut curve in the plane


You now have the profile of your track, with its vertices evenly spaced in Y, to do what you will with - (possibly Duplivert?) whatever suits the rest of your model best.